• Title/Summary/Keyword: V/F Control

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Effects of Voluntary Tutoring and Mandatory Tutoring on Academic Performance

  • Eun Hye KWON;John SMITH;Sukho LEE
    • Journal of Sport and Applied Science
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    • v.7 no.3
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    • pp.27-35
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    • 2023
  • Purpose: Providing tutoring services may be one of the most effective practices for improving academic performance and student retention. However, there is little information on the difference between mandatory tutoring (MT) and voluntary tutoring (VT) on the impact of student academic performance. This investigation compared the effectiveness of VT and MT services in the three upper level undergraduate classes. Research design, data, and methodology: Baseline data were collected in a spring semester where no tutoring of any kind was offered (control group (CG), n=78). The MT (n=104) was required in the following fall semester, and in the next spring semester only VT (n=97) was offered. Descriptive statistics and One-way ANOVA using IBM SPSS v23 (Chicago, IL) were used to analyze the final grades of the courses to identify differences in final grades between semesters. Results: Although final grades averaged from three classes were highest in the MT group, there were no statistical differences between the MT and VT groups, F(2, 292) = 1.150, p =.318. Conclusion: This study indicates there was no significant difference in academic performance between the two tutoring types, but that both tutoring services can be effective.

Molecular Basis of the Hrp Pathogenicity of the Fire Blight Pathogen Erwinia amylovora : a Type III Protein Secretion System Encoded in a Pathogenicity Island

  • Kim, Jihyun F.;Beer, Steven V.
    • The Plant Pathology Journal
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    • v.17 no.2
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    • pp.77-82
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    • 2001
  • Erwinia amylovora causes a devastating disease called fire blight in rosaceous trees and shrubs such as apple, pear, and raspberry. To successfully infect its hosts, the pathogen requires a set of clustered genes termed hrp. Studies on the hrp system of E. amylovora indicated that it consists of three functional classes of genes. Regulation genes including hrpS, hrpS, hrpXY, and hrpL produce proteins that control the expression of other genes in the cluster. Secretion genes, many of which named hrc, encode proteins that may form a transmembrane complex, which is devoted to type III protein secretion. Finally, several genes encode the proteins that are delivered by the protein secretion apparatus. They include harpins, DspE, and other potential effector proteins that may contribute to proliferation of E. amylovora inside the hosts. Harpins are glycine-rich heat-stable elicitors of the hypersensitive response, and induce systemic acquired resistance. The pathogenicity protein DseE is homologous and functionally similar to an avirulence protein of Pseudomonas syringae. The region encompassing the hrpldsp gene cluster of E. amylovora shows features characteristic of a genomic island : a cryptic recombinase/integrase gene and a tRNA gene are present at one end and genes corresponding to those of the Escherichia coli K-12 chromosome are found beyond the region. This island, designated the Hrp pathogenicity island, is more than 60 kilobases in size and carries as many as 60 genes.

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Comprehensive Metatranscriptomic Analysis of Plant Viruses in Imported Frozen Cherries and Blueberries

  • Ga-Eun Lee;Hyo-Jeong Lee;Rae-Dong Jeong
    • The Plant Pathology Journal
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    • v.40 no.4
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    • pp.377-389
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    • 2024
  • The possibility of new viruses emerging in various regions worldwide has increased due to a combination of factors, including climate change and the expansion of international trading. Plant viruses spread through various transmission routes, encompassing well-known avenues such as pollen, seeds, and insects. However, research on potential transmission routes beyond these known mechanisms has remained limited. To address this gap, this study employed metatranscriptomic analysis to ascertain the presence of plant viruses in imported frozen fruits, specifically cherries and blueberries. This analysis aimed to identify pathways through which plant viruses may be introduced into countries. Virome analysis revealed the presence of six species of plant viruses in frozen cherries and blueberries: cherry virus A (CVA), prunus necrotic ringspot virus (PNRSV), prune dwarf virus (PDV), prunus virus F (PrVF), blueberry shock virus (BlShV), and blueberry latent virus (BlLV). Identifying these potential transmission routes is crucial for effectively managing and preventing the spread of plant viruses and crop protection. This study highlights the importance of robust quality control measures and monitoring systems for frozen fruits, emphasizing the need for proactive measures to mitigate the risk associated with the potential spread of plant viruses.

Effect of Paecilomyces fumosoroseus SFP-198 on greenhouse whitefly, Trialeurodes vaporariorum in greenhouse (Paecilomyces fumosoroseus SFP-198의 온실가루이(Trialeurodes vaporariorum)에 대한 살충성 검정과 온실에서의 방제 효과)

  • Shim, Hee-Jin;Kim, Soon-Kee;Yang, Ziwen;Je, Yeon-Ho;Kang, Seok-Kwon
    • The Korean Journal of Pesticide Science
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    • v.3 no.1
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    • pp.90-95
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    • 1999
  • For the control of the greenhouse whitefly, Trialeurodes vaporariorum entomopathogenic fungi were isolated from forest soils and infected insects. We selected three strains, which showed high pathogenicity and named as SFB-582(Beauveria sp.), SFP-198(Paecilomyces fumosoroseus) and SFV-1053(Verticillium sp.) respectively. Particularly, at the concentration of $10^{7}$ conidia/ml, P. fumosoroseus SFP-198 had the highest pathogenicity, $91.4{\pm}3.5%$ in laboratory. In glasshouse application, $91.4{\pm}3.5%$ SFP-198 showed high protective values($80{\sim}90%$) regardless of developmental stages, which were similar with that of Verticillium lecanii F-903 already reported. Four kinds of formulations of entomopathogenic fungi were developed, formulation with surfactant Silwet L-77 gave best control of greenhouse whitefly(over 90%). These results suggest that P. fumosoroseus SFP-198 is a promising candidate as a microbial pesticide for the control of T. vaporariorum.

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Effects of Different Sources of Dietary Chromium on Growth, Blood Profiles and Carcass Traits in Growing-finishing Pigs

  • Park, J.K.;Lee, J.Y.;Chae, B.J.;Ohh, S.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.11
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    • pp.1547-1554
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    • 2009
  • This study was carried out to evaluate the effects of dietary supplementation of different sources of chromium on growth performance, blood profile and carcass trait in growing-finishing pigs. A total of 200 growing pigs (Landrace${\times}$Yorkshire)${\times}$Duroc, average initial weight 8.5 kg) were allotted to 5 treatments with 4 replicates per treatment and 10 pigs per replicate. Five treatments were designated as follows according to the source of chromium. i) Control (No chromium): corn-soybean meal based basal diet, ii) $CrCl_{3}$: control diet+200 ppb Cr as $CrCl_{3}$, iii) CrPic: control diet+200 ppb Cr as Cr picolinate, iv) CrMet-1: control diet+100 ppb Cr as Cr methionine, and v) CrMet-2: control diet+200 ppb Cr as Cr methionine. After the feeding trial, three pigs per replicate (12 pigs per treatment) were slaughtered for the evaluation of carcass traits. Average daily gain (ADG), average daily feed intake (ADFI), and feed: gain ratio (F/G) were not different (p>0.05) among dietary Cr sources. However, whole-period ADG of pigs fed CrPic, CrMet-1 and CrMet-2 diets was higher (p<0.05) than for the control diet. Nutrient digestibility was not different (p>0.05) among dietary Cr sources, but the nutrient digestibility of pigs fed CrPic, CrMet-1 and CrMet-2 diets was higher (p<0.05) than for the control diet. BUN level decreased with more magnitude (p<0.05) in pigs fed Cr during the 20 to 50 kg period. Although both serum cholesterol and triglyceride were different (p<0.05) among treatments, there was no consistent response that could be related to the dietary Cr sources regardless of growth phase. However, the overall data suggested that serum cholesterol level increased as BW of pigs increased. Blood total protein (TP) increased (p<0.05) in pigs fed Cr only during the 90-110 kg phase, and blood creatinine (Creat) level was higher in $CrCl_{3}$ and CrPic treatments than in the control only during the 90-110 kg phase. Backfat thickness was thinner (p<0.05) in pigs fed CrMet-2 than in the control treatment. Therefore, lean percentage was higher (p<0.05) in CrMet-2 than in control pigs. However, dressing percentage and Longissimus muscle area (LMA) were not different (p>0.05) among treatments. In conclusion, dietary supplementation of 200 ppb Cr, via either CrPic or CrMet, improved pig growth performance and nutrient digestibility. Moreover, dietary CrMet supplementation for the growing-finishing pig is evidently remarkable for improving both lean percentage of the carcass and backfat thickness.

A Study on Surface Characteristics and Stability of Implants Treated with Anodic Oxidation and Fluoride Incorporation (양극 산화와 불소 화합물로 처리한 임플랜트의 표면 특성 및 골유착 안정성에 관한 연구)

  • Lim, Jae-Bin;Cho, In-Ho
    • Journal of Dental Rehabilitation and Applied Science
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    • v.22 no.4
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    • pp.349-365
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    • 2006
  • State of problem : A number of investigation about increase of surface area via various surface treatments and modification of surface constituent have been carried out. Purpose : The surface characteristics and stability of implants treated with anodic oxidation, fluoride ion incorporation, and groups treated with both methods were evaluated. Material and method : Specimens were divided into six groups, group 1 was the control group with machined surface implants, groups 2 and 3 were anodic oxidized implants (group 2 was treated with 1M $H_2SO_4$ and 185V, group 3 was treated with 0.25M $H_2SO_4$ and $H_3PO_4$ and 300V). Groups 4, 5 and 6 were treated with fluoride. Group 4 was machined implants treated with 0.1% HF, and groups 5 and 6 were groups 2 and 3 treated with 10% NaF respectively. Using variable methods, implant surface characteristics were observed, and the implant stability was evaluated on rabbit tibia at 0, 4, 8 and 12 weeks. Result : 1. In comparison of the surface characteristics of anodic oxidized groups, group 2 displayed delicate and uniform oxidation layer with small pore size containing Ti, C, O and showed mainly rutile, but group 3 displayed large pore size and irregular oxidation layer with many crators. 2. In comparison of the surface characteristics of fluoride treated groups 4, 5, 6 and non-fluoride treated groups 1, 2, 3, the configurations were similar but the fluoride treated groups displayed rougher surfaces and composition analysis revealed fluoride in groups 4, 5, 6. 3. The fluoride incorporated anodic oxidized groups showed the highest resonance frequency values and removal torque values, and the values decreased in the order of anodic oxidized groups, fluoride treated group, control group. 4. According to implant stability tests, group 2 and 3 showed significantly higher values than the control group (P<.05). The fluoride treated groups showed relatively higher values than the non fluoride treated groups and there were significant difference between group 4 and group 1 (P<.05). Conclusion : From the results above, it can be considered that the anodic oxidation method is an effective method to increase initial bone stability and osseointegration and fluoride containing implant surfaces enhance new bone formation. Implants containing both of these methods should increase osseointegration, and reduce the healing period.

Guidelines for dental clinic infection prevention during COVID-19 pandemic (코로나 바이러스 대유행에 따른 치과 의료 관리 가이드라인)

  • Kim, Jin
    • Journal of Korean Academy of Dental Administration
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    • v.8 no.1
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    • pp.1-7
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    • 2020
  • Dental settings have unique characteristics that warrant specific infection control considerations, including (1) prioritizing the most critical dental services and provide care in a way that minimizes harm to patients due to delayed care, or harm to personnel from potential exposure to persons infected with the COVID-19 disease, and (2) proactively communicate to both personnel and patients the need for them to stay at home if sick. For health care, an interim infection prevention and control recommendation (COVID-19) is recommended for patients suspected of having coronavirus or those whose status has been confirmed. SARS-CoV-2, which is the virus that causes COVID-19, is thought to be spread primarily between people who are in close contact with one another (within 6 feet) through respiratory droplets that are produced when an infected person coughs, sneezes, or talks. Airborne transmission from person-to-person over long distances is unlikely. However, COVID-19 is a new disease, and there remain uncertainties about its mode of spreads and the severity of illness it causes. The virus has been shown to persist in aerosols for several hours, and on some surfaces for days under laboratory conditions. COVID-19 may also be spread by people who are asymptomatic. The practice of dentistry involves the use of rotary dental and surgical instruments, such as handpieces or ultrasonic scalers, and air-water syringes. These instruments create a visible spray that can contain particle droplets of water, saliva, blood, microorganisms, and other debris. While KF 94 masks protect the mucous membranes of the mouth and nose from droplet spatter, they do not provide complete protection against the inhalation of airborne infectious agents. If the patient is afebrile (temperature <100.4°F)* and otherwise without symptoms consistent with COVID-19, then dental care may be provided using appropriate engineering and administrative controls, work practices, and infection control considerations. It is necessary to provide supplies for respiratory hygiene and cough etiquette, including alcohol-based hand rub (ABHR) with 60%~95% alcohol, tissues, and no-touch receptacles for disposal, at healthcare facility entrances, waiting rooms, and patient check-ins. There is also the need to install physical barriers (e.g., glass or plastic windows) in reception areas to limit close contact between triage personnel and potentially infectious patients. Ideally, dental treatment should be provided in individual rooms whenever possible, with a spacing of at least 6 feet between the patient chairs. Further, the use of easy-to-clean floor-to-ceiling barriers will enhance the effectiveness of portable HEPA air filtration systems. Before and after all patient contact, contact with potentially infectious material, and before putting on and after removing personal protective equipment, including gloves, hand hygiene after removal is particularly important to remove any pathogens that may have been transferred to the bare hands during the removal process. ABHR with 60~95% alcohol is to be used, or hands should be washed with soap and water for at least 20 s.

Sensory Evaluation and Changes in Physicochemical Properties of Gochujang Powder with Different Drying Methods (건조방법에 따른 분말 고추장의 성분변화와 관능적 특성)

  • Kim Cheong-Gyu;Lee Jung-Suk;Oh Kyung-Keun;Yi Sang-Duk;Oh Man-Jin
    • Food Science and Preservation
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    • v.13 no.1
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    • pp.24-29
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    • 2006
  • This study was carried out to promote aspects of preservation and convenience of red pepper paste (r.p.p.). Sample was prepared with spray drying (s.d), vacuum drying (v.d) and freeze drying (f.d) methods. The prepared powdered samples were stored for 90 days at $35^{\circ}C$ in seal condition. After powdered samples were hydrated, the samples were used for analysis such as a sensory test, texture, color and changes of component According to sensory test, quality of dried red pepper paste were better in order to f.d.r.p.p. < s.d.r.p.p. < v.d.r.p.p. Changes of pH, reducing sugar, amino nitrogen and NaCl of dried r.p.p. were not observed compared to control but viscosity decreased by about $15\%$ During the storage, acidity decreased by about $15\%$ and reducing sugar, amino nitrogen and ethanol decreased slightly. Hunter L, a and b values decreased from 24.8-27.3 to 23.6-24.4, from 10.8-12.0 to 8.3-9.3 and from 7.1-7.9 to 4.4-5.5, respectively.

Intrinsic Porous Polymer-derived 3D Porous Carbon Electrodes for Electrical Double Layer Capacitor Applications (전기이중층 커패시터용 내재적 미세 다공성 고분자 기반 3차원 다공성 탄소 전극)

  • Han, Jae Hee;Suh, Dong Hack;Kim, Tae-Ho
    • Applied Chemistry for Engineering
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    • v.29 no.6
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    • pp.759-764
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    • 2018
  • 3D porous carbon electrodes (cNPIM), prepared by solution casting of a polymer of intrinsic microporosity (PIM-1) followed by nonsolvent-induced phase separation (NIPS) and carbonization are presented. In order to effectively control the pore size of 3D porous carbon structures, cNPIM was prepared by varying the THF ratio of mixed solvents. The SEM analysis revealed that cNPIMs have a unique 3D macroporous structure having a gradient pore structure, which is expected to grant a smooth and easy ion transfer capability as an electrode material. In addition, the cNPIMs presented a very large specific surface area ($2,101.1m^2/g$) with a narrow micropore size distribution (0.75 nm). Consequently, the cNPIM exhibits a high specific capacitance (304.8 F/g) and superior rate capability of 77% in an aqueous electrolyte. We believe that our approach can provide a variety of new 3D porous carbon materials for the application to an electrochemical energy storage.

Effects of Parameters Defining the Characteristics of Raindrops in the Cloud Microphysics Parameterization on the Simulated Summer Precipitation over the Korean Peninsula (구름미세물리 모수화 방안 내 빗방울의 특성을 정의하는 매개변수가 한반도 여름철 강수 모의에 미치는 영향)

  • Ki-Byung Kim;Kwonil Kim;GyuWon Lee;Kyo-Sun Sunny Lim
    • Atmosphere
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    • v.34 no.3
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    • pp.305-317
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    • 2024
  • The study examines the effects of parameters that define the characteristics of raindrops on the simulated precipitation during the summer season over Korea using the Weather Research and Forecasting (WRF) Double-Moment 6-class (WDM6) cloud microphysics scheme. Prescribed parameters, defining the characteristics of hydrometeors in the WDM6 scheme such as aR, bR, and fR in the fall velocity (VR) - diameter (DR) relationship and shape parameter (𝜇R) in the number concentration (NR) - DR relationship, presents different values compared to the observed data from Two-Dimensional Video Disdrometer (2DVD) at Boseong standard meteorological observatory during 2018~2019. Three experiments were designed for the heavy rainfall event on August 8, 2022 using WRF version 4.3. These include the control (CNTL) experiment with original parameters in the WDM6 scheme; the MUR experiment, adopting the 50th percentile observation value for 𝜇R; and the MEDI experiment, which uses the same 𝜇R as MUR, but also includes fitted values for aR, bR, and fR from the 50th percentile of the observed VR - DR relationship. Both sensitivity experiments show improved precipitation simulation compared to the CNTL by reducing the bias and increasing the probability of detection and equitable threat scores. In these experiments, the raindrop mixing ratio increases and its number concentration decreases in the lower atmosphere. The microphysics budget analysis shows that the increase in the rain mixing ratio is due to enhanced source processes such as graupel melting, vapor condensation, and accretion between cloud water and rain. Our study also emphasizes that applying the solely observed 𝜇R produces more positive impact in the precipitation simulation.